package Example10;

import java.sql.*;
//import java.sql.Connection;
//import java.sql.ResultSet;
//import java.sql.Statement;

public class Example01 {
    public static void main(String[] args)  throws SQLException {
        /**
         * JDBC连接数据库
         * 1.加载 驱动
         * 2.连接
         * 3.表结构
         * 4.预处理（SQL）
         * 5.结果
         * 6.释放 连接
         */
        /**
         * a.
         * b.
         * c.
         * d.
         */
        Statement stmt = null;
        ResultSet re = null;
        Connection conn = null;
        try {
            //1. 注册数据库驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            //2. 通过DriverManager获取数据库连接
            String url =
                    "jdbc:mysql://localhost:3306/jdbc?serverTimezone=GMT%2B8&useSSL=false";
            String username = "root";//数据库账户
            String password = "123456";
            conn = DriverManager.getConnection(url, username, password);
            //3. 通过Connnection对象获取Statement对象
            stmt = conn.createStatement();
            // 4.使用Statement执行SQL语句
            String sql = "select * from useres";
            re = stmt.executeQuery(sql);
            //5.显示结果集合
            System.out.println("id   |   name   |  password   |   email    |   birthday  ");
            while (re.next()) {
                int id = re.getInt("id");
                String name = re.getString("name");
                String pswd = re.getString("password");
                String email = re.getString("email");
                String birthday = re.getString("birthday");
                System.out.println(id+"|"+name+"|" +pswd+ "|" +email+"|"+birthday);
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }finally {
            if ( re  !=null){
                try {
                    re.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                re = null;
            }
            if (stmt!=null){
                try {
                    stmt.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                stmt = null;
            }
            if (conn!=null){
                try {
                    conn.close();
                }catch (SQLException e){
                    e.printStackTrace();
                }
                conn = null;
            }
        }
    }
}